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Microstructure and texture formation were investigated in an intermetallic Ti–43.4Al–4.2Nb–1.1Mo–0.1B (in at.%) alloy after near conventional forging in the (α + β) phase field region and subsequent isothermal annealing treatments at 1150 °C for different holding times. During forging and the following cooling process a fine grained microstructure is formed consisting of lamellar α2/γ colonies and elongated grains of the βo phase situated at the colony boundaries. The isothermal annealing treatment leads to a significant change of the forged microstructure. After hot-forging, all phases show typical fiber textures as it is expected for uniaxial deformation. In the as-forged state the α2(α) phase exhibits a 〈11-20〉 fiber, the βo(β) phase has a strong and sharp fiber and the γ phase shows a and a weaker fiber. After additional annealing at 1150 °C for 8 h, the textures are almost unchanged in contrast to the microstructure.

The formation of textures in DNA films with LiCl, NaCl, KCl, RbCl, and CsCl salts has been studied. The films are prepared by evaporation of water solution with highly polymerized calf thymus DNA and excess salt of specific type. For DNA solution with 10 mM concentration of NaCl, KCl, and RbCl the films with dendritic textures have been obtained, whereas in case of CsCl the textures in the films appear only at 30 mM concentration of excess salt in the initial solution. In the solution with LiCl, the textures in DNA films have not been observed within the whole range of concentration of excess salt under consideration. The analysis of parameters of DNA films with different salts has showed that evaporation of solution leads to crystallization of salt ions on DNA macromolecule and formation of DNA-salt complexes. Electrostatic energy of the system of crystalline ordered ions and charges of DNA chains has been estimated to study the stability of DNA-salt complexes. The results obtained for different salts have been showed that the presence of DNA macromolecule enhances crystallization as compared with solution without DNA. The property of excess salt to form the crystalline structures has been found to decrease in the following order: KCl > NaCl > RbCl > CsCl > LiCl. The results of estimation are in good agreement with the experimentally observed dependence of texture formation on excess salt type.

The effect of friction on evolution of the microstructure and texture during hot rolling in the ferrite region was studied with secondary electromicroscopy (SEM), X-ray diffractometer, and FEM simulation. The friction between a roll and a steel sheet surface leads to the formation of notable through-thickness texture gradients. The finite element method (FEM) simulation shows that the large friction coefficient between a roll and sample results in a pronounced variation of (shear strain rate) and large e13/e11 value which accounts for strong {110} texture components and weak γ-fiber components at rolled sheet surface; whereas the friction condition do not exert notable effect on texture formation at the sheet center.

The formation of texture and its influence on some mechanical properties of retaining rings manufactured from stainless austenitic CrMnN steel were studied. It was found that different crystallite orientations prevail in tangential, radial and axial direction of the retaining ring as a result of plastic deformation by cold expansion. The change of texture from the inner to the outer diameter of the ring occurs because of a decreasing deformation. The formation of texture causes an anisotropy of mechanical properties. Texturbildung und Anisotropie der mechanischen Eigenschaften von Kappenringen aus austenitischem CrMnN Stahl Es wurde die Texturbildung und ihr Einfluss auf einige mechanischen Eigenschaften von Kappenringen aus nichtrostendem austenitischem Stahl untersucht. Es wurde festgestellt, dass unterschiedliche Kristallorientierungen in tangentialer, radialer und achsialer Richtung der Ringe als Ergebnis plastischer Verformung beim Kaltaufweiten vorherrschen. Wegen abnehmender Verformung andert sich die Textur vom inneren zum ausseren Ringdurchmesser. Die Texturbildung fuhrt zur Anisotropie der mechanischen Eigenschaften.

The Laser Zone Melting (LZM) method was used to produce pure and MgO-doped, textured Bi2.03Sr1.93Ca1.07Cu2.05O8+δ superconducting flat monoliths. Grain alignment was studied by XRD on the surface of both textured products as a function of annealing time and MgO content. Grain angle boundaries were found in all cases to be below 10° on the surface of all samples. Phase formation was studied during annealing after LZM, suggesting that formation of the 2212 phase takes place at faster rates in samples containing MgO. AC Magnetic Susceptibility studies were performed on annealed samples in order to determine Tc and Jc values. The transition temperatures remained approximately constant, while the critical current density values increased by a factor of 3 when MgO was present. Laser-Zonenschmelzung und Texturbildung in MgO-dotiertem Bi2.03Sr1.93Ca1.07Cu2.05O8+δ Die Laser-Zonenschmelz-Methode (LZM) wurde zur Darstellung von reinem und MgO-dotierten, supraleitenden Schichten von Bi2, 03Sr1, 93Ca1, 07Cu2, 05O8+δ genutzt. Die Kornausrichtung wurde durch Rontgenbeugung an den Oberflachen von beiden Produkten in Abhangigkeit von Temperzeit und MgO-Gehalt untersucht. In allen Fallen waren die Kornwinkelgrenzen unter 10° an den Oberflachen aller Proben. Die Phasenbildung wurde wahrend des Erhitzens durch LZM untersucht und ergab, dass die Bildung der 2212-Phase in den Proben mit MgO schneller erfolgte. Messungen der magnetischen Suszeptibilitat wurden an getemperten Proben zur Bestimmung der Tc- und Jc-Werte ausgefuhrt. Die Ubergangstemperaturen blieben annahernd konstant, wahrend die kritische Stromdichte um den Faktor 3 in Gegenwart von MgO zunahm.

In the so-called ferritic rolling the finishing is shifted down into the temperature region of ferrite, which enables a production of thinner hot strips (compared to the conventional hot rolling in austenite) with a changed texture development. The present study is focused on the effect of the process parameters of such initial warm rolled hot strips on the texture formation and hence on the deep-drawing quality of the final cold strips. A special attention is given to the transmission of the hot strip texture to the cold strip. The investigation was carried out on commercial IF- and ELC-steels by a laboratory simulation with the hot deformation simulator Wumsi (rolling simulated by the plane strain compression test). It was possible to optimize cold rolling and subsequent annealing by means of the measurements of the texture development during the ferritic (warm) deformation as well as the parameters of the processing route of such special production of cold strips by means of the calculation of r-values. If compared with the conventional processing route, a considerable improvement of deep-drawability with a diminished earing is achievable especially with the IF-steel.

Texture formation via high-temperature deformation in sintered alumina was investigated. Fine-grained, normal-purity-alumina sintered bodies deformed under stresses up to 80 MPa in a temperature range of 1200°–1300°C. Fine, disklike grains formed in the equiaxial fine-grained matrix during high-temperature deformation and aligned unidirectionally via material flow during deformation. Highly textured sintered alumina bodies were obtained via high-temperature deformation and further annealing.

The surface segregation of antimony was studied using AES on a 1.8% Si steel alloyed with different mass contents of Sb (0.052 and 0.1%). The dependence of surface segregation on grain orientation and on the presence of other solute atoms (S, P, C, Al, Si) were investigated under UHV conditions in the temperature range from 450 to 900° C. The results lead to an explanation for the formation of a texture rich in (100)-grains in Si steel caused by the presence of Sb. Also grain boundaries were analysed by AES after annealing at 850, 700 and 550° C for different times. Since the grain boundary segregation was negligible one can conclude that the texture formation results from orientation dependent surface segregation of Sb causing differences in surface energies and stabilities of different grains

A correlation is revealed between texture, grain morphology, and impurity content in polycrystalline Al films. The 〈111〉 texture at low contamination level develops by restructuration while in the case of mixed 〈111〉 and 〈100〉 textures the 〈111〉 part develops by restructuration and the 〈100〉 part by competitive growth controlled by impurities.

The role of the recrystallization in the processes of microstructure and texture formation of silver films is compared for films: 1) deposited at high substrate temperatures (up to 720 K) and slowly cooled or quenched to room temperature; 2) deposited at room temperature and annealed at high temperatures. The grain growth distribution curves and the texture perfection are analysed. It is shown that the recrystallization processes taking place both during the slow cooling and during the annealing of the films lead to a formation of identical film structure with lower degree of texture perfection than in the case of quenched films

The texture formation in quenched γ-phase Mn-Cu alloys at cold rolling have been studied. It was found that the final texture in martensitic Mn-10% Cu alloy consists of nearly equal volume of {001}〈100〉 and {112}〈111〉 texture components. A sharper {101}〈121〉 component in small amounts can be present too. In austenitic Mn-22% Cu alloy the {112}〈111〉 component is more scattered and weakened, and the strong {101}〈121〉 component has formed. In the Mn-30% Cu alloy the {001}〈100〉 component is almost absent, {112}〈111〉 is very weak and the {101}〈121〉 texture is dominated. [Russian Text Ignored].

The band texture formation of nematic poly(1,4-phenyleneterephthalamide) (PPTA)/H2SO4 solutions after shearing between rotating plates was studied. For a thickness of the solution layer larger than 20 μm the band texture appears immediately after the cessation of shearing, but a critical shear rate is needed which was demonstrated directly using polarizing microscopy. When the solution-layer thickness was less than 10 μm, an induction time tb needed for the development of the band texture after the cessation of shearing was observed, which was of the order of 10 to 102 s. It is thus shown without any ambiguity that the band texture is formed during relaxation of shear orientation. The effects of solution concentration, solution-layer thickness, shear rate, and shearing time on tb were studied. Once the band texture is formed from a sheared solution, it will take hours to relax completely to a randomly oriented domain texture. The factors influencing this relaxation time were also studied.

A new method to obtain multi-domain textures in homeotropically aligned nematic liquid crystal displays is proposed and the mechanisms responsible for texture formation are described. We present textures and electrooptic properties for various possible pixel geometries.

For perpendicular magnetic recording layers the c-axis inplane components and the effective uniaxial anisotropy are calculated in dependence on the angular width of the c-axis texture as well as on the amount of parasitic non c-axis textures. Taking into account an inhomogeneous distribution of the texture, i.e. a transition layer within the film experimental observations in the literature may be well understood. The dependence of magnetic characteristics on the film thickness is evaluated. It is shown that film quality has to be characterized by the full texture distribution function rather than by texture half width alone. Im Fall von Schichten fur die magnetische Senkrechtspeicherung werden die c-Achsen-Komponenten in der Schichtebene und die effektive einachsige Anisotropie in Abhangigkeit sowohl von der Winkelbreite der c-Achsen-Textur als auch von dem Anteil parasitarer Texturen berechnet. Dabei kann unter Berucksichtigung einer inhomogenen Verteilung der Textur, d. h. einer Ubergangsschicht, eine gute Verifizierung experimenteller Ergebnisse aus der Literatur erreicht werden. Die Abhangigkeit der magnetischen Parameter von der Schichtdicke wird bestimmt. Es wird gezeigt, das zur Charakterisierung der Schichtqualitat nicht nur die Halbwertsbreite, sondern die vollstandige Textur-Verteilungsfunktion erforderlich ist.

Studied are the regularities of preferred orientations in the process of rolling of zinc, magnesium, and cadmium. On the basis of the data obtained and analysis of crystallographic mechanism of Cd, Zn and Mg crystals a “dynamic” model of the rolling texture formation in zinc and cadmium as well as a “monotonic” one in magnesium are suggested. Es werden die Gesetzmasigkeiten bevorzugter Orientierungen beim Walzen von Zink, Magnesium und Cadmium untersucht. Auf der Grundlage der erhaltenen Werte und einer Analyse des kristallographischen Mechanismus von Cd-, Zn- und Mg-Kristallen wird ein „dynamisches” Modell der Walztexturbildung in Zink und Cadmium sowie ein „monotones” fur Magnesium vorgeschlagen.

In the present paper a quite general approach is proposed for the problem of the formation of the prefered orientations (i.e. of the texture). The rotation field is considered by the present authors as the most general variable which describes completely the texture formation process. The proposed continuity equation transforms immediately the rotation field to the texture function (Orientation distribution function). The presented formatlism is illustrated by a few f.c.c. rolling textures. Dans ce travail nous avons presente une approche tres generale au probleme de la formation des orientations privilegiees (texture). Le champ de rotation est considere ar les auteurs comme une variable la plus generale qui determine entierement le processus de la formation de la texture. L'equation de continuite proposee permet une transformation directe du champ de rotation en fonction de texture (fonction de distribution des orientations cristallines). A titre d'exemple, nous presentons quelques textures c.f.c. prevues avee notre formalisme.

The texture formation, at each machining stage, in the CT45, CT50 and CT40X steels machined via two technological alternative ways has been investigated, these being as follows: (1) turning — grinding — superfinishing, (2) turning — hardening — grinding — superfinishing. Presented are the (110) pole figures obtained by the reflection method. It was shown that the grinding and superfinishing of the specimens in compliance with the alternative way 1 led to formation of the texture, the basal ideal orientations of which resemble that of rolling one for the [Russian Text Ignored].-metals. The recrystallization (110) [001] component is therewith also contained in the grinding texture. No texture was recognized in specimens machined by the procedure according to the alternative way 2. These facts being accounted for by the pressure and temperature factors operating in the course of grinding and superfinishing, as well as by the dependence of the deformation mechanism of the steels under study on a preliminary machining of the latter. Folgende technologische Alternativwege wurden zur Untersuchung der Texturbildung in jeder Bearbeitungsstufe an CT45, CT50- und CT40X-Stahlen eingeschlagen: 1. Drehen — Schleifen — Feinstziehschleifen, 2. Drehen — Harten — Schleifen — Feinstziehschleifen. Vorgestellt werden die (110)-Polfiguren, die mit Hilfe der Reflexionsmethode erhalten wurden. Es wird gezeigt, das das Schleifen und Feinstziehschleifen der Proben nach dem Arbeitsgang 1 zur Bildung einer Textur fuhrt, deren ideale Grundorientierungen der Walztextur von OZK-Metallen ahnelt. Die (110) [001] Rekristallisationskomponente ist dadurch auch in der Schleiftextur enthalten. Keine Textur wurde beobachtet in Proben, die nach dem Arbeitsgang 2 bearbeitet wurden. Dieser Befund wird dem Druck und der Temperatur zugerechnet, die im Verlaufe des Schleifens und Feinstziehschleifens herrschen wie auch der Abhangigkeit des Verformungsmechanismus der Stahle von ihrer vorhergehenden Bearbeitung.

1. Processes of texture formation were studied in three NiFe system alloys containing Mo and Ti (alloy No. 1), Cr, Ti and Al (alloy No. 2) and Co, Ti and Al (alloy No. 3). The deformation texture is identical in all alloys which agrees with the proximity of stacking fault energies as estimated from X-ray data. 2. Annealing leads to a pronounced diffusion and alteration of the texture in alloy No. 1, but does not alter the texture type and intensity in alloy No. 2, whereas in alloy No. 3 the typical strain texture components are intensified. 3. Structure processes governing texture formation were identified as recrystallization in alloy No. 1, and oriented γ–γ′ transformation in alloys No. 2 and 3 where the intergranular boundaries were blocked by heterogenous precipitation of phases not possessing fcc structure.

Scanning electron and transmitted light microscopy were used to study the role of crude fiber in texture formation during non-extrusion processing of soy flour. By comparing micrographs of texturized soy flour, water-extracted texturized soy flour, texturized soy concentrate, texturized soy isolate, and texturized soy product-hull blends, transmitted light and scanning electron microscopy showed that removal of the soluble carbohydrate fractions either before or after nonextrusion texturization did not alter the morphology or microstructure of the texturized soy concentrate or water-extracted texturized soy flour as compared to texturized soy flour. Therefore, it seems probable that the presence of the soluble carbohydrate fractions is not a prerequisite for the formation of the alveolate morphology normally created during nonextrusion processing. Scanning electron microscopy showed that the cuticle morphology of the texturized soy isolate's alveoli was changed as the amount of crude fiber in the soy hull-soy isolate blend increased. The cuticle morphology of the texturized soy isolate-soy hull blend was similar to that of the texturized soy concentrate and texturized soy flour. Therefore, crude fiber seems to control the type of alveolation developed and the type of cuticle morphology exhibited in the product's alveoli.

The program of studies carried out in the Institute of Fundamental Technological Research concerning fundamentals of polymer crystallization and orientation is briefly described. Discussions center on studies of polymer texture formation caused by complex external conditions.